Multi-scale Assessment of Riverscape Complexity (MARC) Project

Throughout the Northern Rocky Mountains, Pacific Northwest, and North Pacific Rim, large alluvial floodplains of gravel-bed rivers are enormously complex and include physically and biologically diverse riparian and aquatic habitats. The Multi-scale Assessment of Riverscape Complexity (MARC) Project is linking remote sensing of floodplain complexity to niche composition, microbial diversity, and ecosystem functioning across Montana’s riverscapes. Our approach has been to couple assessment of floodplain complexity to heterogeneity in aquatic environmental conditions, microbial diversity, and variation in ecosystem functions like primary production and respiration. Using airborne hyperspectral instruments, we have collected over 5000 images of 10 riverscapes distributed across Montana’s sentinel physiographic provinces (Crown of the Continent, Upper Missouri, Greater Yellowstone, Northern Plains). At the same time that images were collected by aircraft, field crews collected nearly 400 samples from the rivers and floodplain aquatic habitats in order to tie physical, chemical, and biological character to ecosystem type and location. When quantitatively linked, the relationship between riverscape complexity and the diversity of biological form and function may be used to extend our understanding of the biocomplexity of Montana’s river systems and how human influences like flow regulation and floodplain development may alter ecosystems services associated with these threatened landscapes.